A war is brewing in India between the nation's coffee and tea industries over which drink should be declared the national beverage.

While coffee's popularity is rising among the nation's growing middle class, tea has history on its side.

Zach Marks is travelling to every state in India with fellow researcher Resham Gellatly, documenting the lives of the country's chai wallahs, or tea vendors.

"On our first trip to India, we would go to new places, and when we would want to meet local folks we would just go to the chai stand," he said.

"That is where everyone gathers and there is a real community there so it is a great way to learn about a place through the lens of the chai stand."

Chai recipe

There is no fixed recipe or preparation method for masala chai and many families have their own versions of the tea. Here's one example:Ingredients1 1/2 cups of water1/2 inch stick of cinnamon8 cardamom pods1/2 teaspoon of cloves1/4 inch of fresh ginger root, thinly sliced1 cup of milk6 teaspoons sugar3 teaspoons of Darjeeling tea leaves

MethodPlace water, cinnamon, cardamom, cloves and ginger in a pot and bring to a boil.Cover and lower heat to low setting and simmer for 10 minutes.Add milk and sugar and again bring to a simmer.Next, add the tea leaves, remove from heat and cover.Let steep for three minutes and strain. Enjoy!

Ms Gellatly says while the hot, spicy beverage is seen as uniquely Indian, it's actually a relatively new phenomenon.

Tea was introduced by the British East India company in the 1800s.

"Before that Indians drank a concoction that had ginger and the spices normally found in masala chai - but tea didn't come until much later," Ms Gellatly said.

Mr Marks says the chai stand is even more recent.

"It was really in the 20th century that the British East India Company and British tea merchants decided there was a big Indian domestic market for this stuff, so they started trying to cultivate Indian demand," he said.

"One of the ways they would do that is they would go to these Indian railway stations and serve free tea and milk."

Over the past century Indians have truly made tea their own, and the chai wallah has become an integral part of Indian life.

"At chai stands at the village, for example, there might be one person in the village that is literate," Ms Gellatly said.

"At the chai stand he will read the newspaper to all the other villagers who gather around and hear the daily news.

At his chai stall at Delhi University, Deepu makes hundreds, maybe thousands of cups of chai each day.

It's exam time and the students couldn't be more grateful for a cup of sweet, milky chai.

"Deepu is not just the chai wallah - he is their friend," Mr Marks said.

"You can see this if you look at this booklet which Deepu has, in which his long-time customers and students write little notes as just a way to keep in touch.

"If you look through this book there are all these poems and songs and odes written to Deepu's chai."

While chai has a deep place in the hearts of India, modernisation and urbanisation is threatening the traditional chai stall.

"Basically these chai wallahs have these temporary stalls that they set up, [others] kind of go around with their kettles and cups and don't have a stall [and] others put something up that can be taken down easily," Ms Gellatly said.

"And unfortunately, sometimes, the police do evict chai wallahs from their spots."

And as the country changes, so too does its palate.

Coffee consumption in India grew five per cent last year, while tea production slumped, and Ms Gellatly says coffee chains like Starbucks have other appealing qualities.

"They are very appealing especially to the young modern Indians because they have air-conditioning, they have Wi-Fi, they are a safe space for men and women to hang out together," she said.

The Indian Government is now considering naming tea as the national drink, in the hope of boosting its popularity at home and abroad.

The coffee industry isn't happy, but it has a hard case to make against the drink many consider to be a staple of Indian life.